Grönhögen was developed during the 1700's to an important shipping harbour for the quarries on southern Öland. Development of the harbour followed a natural pattern similar to that of other harbours on Öland. The origin was a bay or a beach, where the flat-bottomed boats could be pulled ashore. Then a long, simple wooden pier was built, that was owned and maintained by the local farmers. It was later substituted for a stone pier. In those days the ships mostly sailed to Karlskrona with limestone because of the building of a harbour and fortress there. From the late 19th century there was a scouring work of the northern Öland model in Grönhögen, which manufactured floor stones for export. Between 1918 and 1921 the harbour was expanded with mooring places and piers. The limestone from Öland was not suitable for the construction, instead granite had to be fetched from Blekinge. The harbour gained status as a support harbour for fishing in the Baltic and as such it held great importance to the salmon fishing. The status of the harbour later led to the development of an Ytong factory (1939-1971) on the location, thus giving the Grönhögen ships a freight base. Yet today, Grönhögen harbour, by virtue of its location, is an important fishing- and leisure harbour.

The coast around southern Öland is treacherous with projecting sandbanks that have always caused a problem for ships. In Grönhögen there is also a sea rescue station, which was founded already in 1912 as the third rescue station in the country. The former boathouse is now remodelled into a summer café.